Brazing is one of the known method of joining metal members together with a brazing filler, i.e., a metal or alloy having a lower melting point than the metals to be joined. Brazing typically involves the use of a torch having at least two needle metering valves that control the flow and ratio of at least two welding gases. One of the gases will include a flammable fuel gas such as LP gas, natural gas, acetylene gas, methane, propane, butane, hydrogen and mixtures and combinations thereof, while the other gas will include a combustion-assisting gas such as oxygen or air. Needle metering valves are used to manually adjust the flow of the gases before and during brazing because the pressure, flow rate, and/or quality of the gases can vary and, in some cases, lead to quality issues. Adjustment is needed due to a variety of reasons, including changes in external temperature, the total amount of gas used, or the amount of gas remaining in a cylinder, all variables which affect gas flow rates. In addition, a torch operator, even an operator with many years of experience, can have a very difficult time setting the needle valves and determining if the gas mixture creates a flame having an acceptable oxygen to fuel ratio.
In view of the foregoing problems and shortcomings of existing brazing systems with torches having a plurality of adjustment valves, the present application describes a brazing system and method to overcome these shortcomings.